What caused the March 25, 1998 Antarctic plate earthquake?:
Inferences from regional stress and strain rate fields
Corné Kreemer and
William E. Holt
(SUNY Stony Brook)
We investigate the possible driving forces behind the occurrence of the 1998 Antarctic
plate earthquake. We determine first a regional strain rate field associated with the accommodation
of relative motion, and second, a vertically averaged minimum deviatoric stress field associated with
lithopsheric gravitational potential energy differences and deglaciation of the Antarctic ice cap.
We find that the mechanism of the event is inconsistent with strain orientations inferred from
kinematic modeling of a diffuse zone of deformation within the triple junction region.
Stress perturbations associated with deglaciation cannot be ruled out as a triggering mechanism of
this event.